When installing a yard hydrant, knowing your hydrant and waterline depth is one of the most important aspects in the installation process. To answer the question “How deep should I bury a yard hydrant”, you need to know how deep the ground can freeze in your location. In the continental US, frost depth can range from region to region. The lowest is 0 feet, where the ground never freezes (think southern California) to 8’ deep (think northern Minnesota). Frost-proof hydrants are used in locations where the ground freezes. This ensure that hydrants can be used in the dead of winter in the toughest of conditions.
All big brand hydrants claim to be “frost-proof” however a hydrant is only “frost-proof” if it is installed with the base of the hydrant and the waterline below the frost line. The frost line is the deepest point where the ground is frozen at any given time. The map below shows how deep frost will get during an average winter. Most professionals will know how deep the frost was on the coldest winter and will install the hydrant valve below that point. Most years the frost won’t be anywhere near the base of the hydrant. However, on those really cold winters, your hydrant will still work if it’s installed at the proper depth.
If you still aren’t sure how deep your water lines should go, a great resource is a local well driller. They will know what the standard depth for a waterline is in the area.
Everything Below the Frost Line
The final step is making sure the entire waterline is below the frost line. If you bury your hydrant deep enough, but the waterline ends up too shallow, this can be a problem. You may find yourself in a situation where your waterline is frozen and no water can get through, but your hydrant is not frozen. The hydrant will still open and close but won’t produce any water. It’s important to ensure that your waterline is deep enough from the source all the way to the hydrant. If any sections end up in frozen ground, the water in that section of waterline will freeze. If the waterline is frozen, no water will be able to come out of the hydrant. This a problem you don’t want to have during the coldest week of the year. Be sure to check your depths when installing your yard hydrant and waterlines!
Upgrade Your Hydrant
If you are thinking about installing a hydrant, or are simply repairing or replacing your old hydrant, check out our “All About the HAK” page to find out more about how to upgrade your hydrant!
If you enjoyed this blog, we will be posting one every other Friday so check back in two weeks to find out more about how to size a waterline.